Hi everyone, this is my first post. Great website, excellent info! We have been reading a lot and my wife and I are very excited about getting a little GSP. We've set up a new 27 gallon cube as a brackish setup (1.010), with the intent to eventually move to full marine. We've done a lot of research and I think we're ready! My question has to do with the tank cycle.

To initiate the cycle I placed some gravel in the tank from an established aquarium, and established filter media in the aquaclear HOB filter. We took it to the LFS to test it after a week and got 0 ammonia, 0 nitrite, and 0 nitrate. As there are no nitrates showing up, we can't be sure it has cycled. We ended up buying a couple of mollies to aid with the cycle if necessary. My question is about using the gravel/media I used. They were from a freshwater setup, and I just dropped them in (no acclimation). Do you think that would have killed the bacteria? Am I starting fresh with a cycle and these mollies? The mollies are doing okay, but very shy and are barely eating. It seems at this rate it could be long time before we can add our little puffer. Any input/advice is appreciated. We're just a little anxious to get the little guy, but want to do it right. In hindsight, I think I should have cycled it as fresh.

Hello.If you took stuff from your established freshwater tank and put it in your 1.010 brackish tank, then there is a big enough difference to kill all the bacteria on the stuff from your established tank. Your next purchase should be a test kit. Instead of buying mollies, it would've been cheaper to buy a bottle of ammonia from Ace Hardware for fishless cycling. Consider it if you ever try to set up another new tank.

We will upgrade the tank eventually, but everything we read said around 30 gallons was enough for a single GSP. I can see how it would seem crowded when he's the size of a pop can.

As for the ammonia, wish that was something I would have read earlier. I read everything I could about cycling, and never read that....swell. I even discussed the topic at my lfs, they suggested the gravel technique. I usually try to read what's already out there instead of posting things that have been discussed. Guess I should have posted instead. :\ I can still remove the mollies and transition them to my freshwater community tank. How long should I expect using pure ammonia? And how much to add?

bighex wrote:How long should I expect using pure ammonia? And how much to add?

A few drops every other day until 0 ammonia and nitrIte with lots of nitrAte. If you do it precisely, then cycling can be achieved in 2-3 weeks. If you do it the easy way (not done precisely), then it could take up to 4-5 weeks. There's an article somewhere on this about fishless cycling.

I can get some gravel from an established brackish tank. I was surprised to hear how long it takes. I was told the tank would cycle in a week or so just by adding an established bacteria colony. I can see now that you would need to add the ammonia to complete the process. I assume the more bacteria I add, the faster it will cycle. Is that correct? For example; if I can an established sponge filter along with the gravel, it would be better than gravel alone.

yes, the more bacteria you have the better. How ever the source of the bacteria is very important as it can bring diseases/sickness if it's not from a healthy aquarium. Next, gravel does hold some bacteria, but not as much as filter media.

"Obstacles are those frightful things you see when you take your eyes off your goal." -- Henry Ford

Fish can be drip-acclimated; bacteria cannot. FW and very low BW bacteria and mid-range to full SW bacteria are entirely different species. It is not a matter of aclimating them to the water, you must grow entirely new colonies of different bacteria.

Many free-living soil- or water-dwelling bacteria grow quite rapidly. Obligate attached bacteria tend to slower. Niytrification bacteria are obligate-attached types and among the slower growing forms. Two separate species are required (one oxidizes ammonia to nitrite, the other oxidizes nitrite to nitrate. Under the very best conditions you may get a little more than one population doubling per day, but in fresh setups you cannot count on that. Minimum cycling time (from inoculation to mature colonies) is 10 to 12 days, and that ordinarily requires very large inoculations and at least daily water testing and adjustments as needed. Two to three weeks is about the minimum time for other than very experienced hobbyists, a moth about average for most hobbyists. It can take longer than that.

The fish is in BW at the shop, at 1.010. The cycling is going slow, and yes I understand patience is important. I've been keeping fish in one form or another for over 30 years. You would think I'd have a better grasp on the nitogen cycle by now! I've had freshwater tanks continually operating for so long I haven't had to cycle one, and marine tanks were pretty simple to cycle with live rock. I'm learning some good stuff, I appreciate all the help and information on this board.

I am using the household ammonia method now, started last Thursday. I brought it up to about 4-5 ppm and it has gone down very slowly. Added a little more ammonia yesterday. I bought a used sponge filter from a BW tank at my lfs which I added about a week ago. Now it's just test, monitor and wait. Now at least I'll have a head start on the snail jail! That's been going for about two weeks, maybe I'll have some babies in a couple more.

I have to admit that I have never cycled a BW tank from scratch as a BW tank. I have always started with a FW mature filter and slowly raised it to BW. I have done SW filters from scratch, but that has been a long time ago.